cross-posted from: https://lemm.ee/post/5467810

In 1997, a contest began to develop a new encryption algorithm to become the Advanced Encryption Standard. After years of debate, one algorithm was chosen as the AES. But how does AES work? And what makes for a secure encryption algorithm?


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  • 0:00 The Contest
  • 1:02 Encryption
  • 3:57 Confusion and Diffusion
  • 5:44 Block Cipher
  • 6:55 KeyExpansion
  • 7:34 AddRoundKey
  • 8:14 Substitution Cipher
  • 8:55 SubBytes
  • 11:30 MixColumns
  • 12:53 ShiftRows
  • 13:21 The Algorithm

Aug 22, 2023